X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=rpikern;a=blobdiff_plain;f=src%2Fserial.c;fp=src%2Fserial.c;h=ddd5923da5b59d0b99ac3925237c699f01a71c1c;hp=0000000000000000000000000000000000000000;hb=9a3655a43358c43128f6e62c8d74ff3aa81960c7;hpb=322d8fe4bf7ecd74ffb5288539efd3db828aa72a

diff --git a/src/serial.c b/src/serial.c
new file mode 100644
index 0000000..ddd5923
--- /dev/null
+++ b/src/serial.c
@@ -0,0 +1,54 @@
+#include <stdint.h>
+#include "serial.h"
+#include "uart.h"
+#include "gpio.h"
+
+/* baud rate: BAUDDIV = (UART_CLK / (16 * baud)) */
+#define UART_CLK	3000000
+
+void init_serial(int baud)
+{
+	uint32_t bdiv_fp6;
+
+	REG_CR = 0;		/* disable UART */
+
+	/* disable pullups for GPIO 14 & 15 */
+	gpio_pullups(0xc000, 0, PUD_DISABLE);
+
+	REG_ICR = 0;	/* clear pending interrupts */
+
+	/* calculate baud rate divisor */
+	bdiv_fp6 = (UART_CLK << 6) / (16 * baud);
+	REG_IBRD = (bdiv_fp6 >> 6) & 0xffff;	/* 16 bits integer part */
+	REG_FBRD = bdiv_fp6 & 0x3f;		/* 6 bits fractional precision */
+
+	/* line control: fifo enable, 8n1 */
+	REG_LCRH = LCRH_FIFOEN | LCRH_8BITS;
+	/* mask all interrupts */
+	REG_IMSC = I_CTS | I_RX | I_TX | I_RTIME | I_FRM | I_PAR | I_BRK | I_OVR;
+
+	/* enable UART RX&TX */
+	REG_CR = CR_UARTEN | CR_TXEN | CR_RXEN;
+}
+
+void ser_putchar(int c)
+{
+	while(REG_FR & FR_TXFF);
+	REG_DR = c & 0xff;
+}
+
+int ser_getchar(void)
+{
+	while(REG_FR & FR_RXFE);
+	return REG_DR & 0xff;
+}
+
+void ser_printstr(const char *s)
+{
+	while(*s) {
+		if(*s == '\n') {
+			ser_putchar('\r');
+		}
+		ser_putchar(*s++);
+	}
+}